Aluminum alloy



Patented Jan. 15, 1224.

ALFRED voN ZEERLEDER, 0F NEUHAUSEN, SWITZERLAND, ASSIGNOR T0 ALUMINIUM-IN'DUSTRIE-AKTIENGESELLSCHAFT, OF NEUHAUSEN, SWITZERLAND,

CORPORATION.

A SWISS ALUMINUM ALLOY.

No Drawing.

- for making sheets are improved by adding to it copper. in variousquantities. In America, an alloy havlng about 8% copper is veryextensively used for making castings for the automobile industry and forsimilar purposes. On the other hand, 2% to 5% copper is frequently addedfor making sheets, whereby the strength is materially increased. 7

Further, in the metallurgy of aluminum and its alloys, it has heretoforebeen universally held that a greater percentage of iron than thatcontained in ordinary commercial aluminum has a prejudicial effect.According to Schiermeister (Stahl & Eisen, page 87 1) ironaluminumalloys will hardly acquire technical importance.- According to Zeerleder(Metall & Erz 1917, page 330), iron has an injurious influence on thestrength of aluminum and its alloys, and the percentage of iron musttherefore be kept as low as possible. of the United States of Americaconfirms these statements in its Circular No. 76.

An aluminum alloy according to this invention contains both copper andiron, the iron content exceeding one and one-half per centum of thealloy, and amounting, in some mixtures, to even four per centum 1%)thereof, and the alloy containing approximately twice as much copperasit does iron. Contrary to expectations, this alloy is particularlyvaluable owin to its strength, and is especially suitable or makingcast- The Bureau of Standards Application filed February 10, 1922.Serial No. 535,655.

ings. An alloy with 1.75 %2.75% iron with -3.5%4.5% copper isparticularly advantageous. For example, sand casting with 20% iron and3.7% copper have been found to have a tensile strength of 19 kg. per sq.5

mm. and 5% extension, a result not obtainable with other alloys of aboutthe same specific weight, andnot even with chill mould castings.

The new alloy. can be advantageously rolled and drawn, and strengths of38 kg. per

sq m m; and upwards can be obtained. That it is possible to obtain sucha strength by employing admixtures that can be obtained readily and at alow cost, is of great importance commercially in connection with the useof the alloy. It is to be understood that the alloy may also contain theusual means for further improving its physical properties,

such as, for example, an admixture of man- 6 ganese, nickel, titanium,num, magnesium, cerium, the equivalents of these metals, in quantitiesof 0.1% to 2% of the total, and in addition,

wolfram, molybdeits quality can be improved by heat treatment.

I claim:

1. An aluminum-copper-iron alloy consisting of from 88% to 95% aluminum,the remaining per and iron in the relative proportions of two parts ofcopper to one part of iron, approximately.

2. An 'aluminum-copper-iron alloy consistim of from 92.75% to 94.75%aluminum 8C the remaining 7.25% to 5.25% being made up of copper andiron, in the relative proportions of 2.75% to 1.75% iron, to 41.5% to3.5% copper.

In testimony whereof, I attixmy signature 85 in the presence of twowitnesses.

DR. ALFRED VON ZEERLEDER.

- Witnesses:

D. JULIUS WEBER, HANS HAUUrE.

chrom um, and I 12% to 5% being made up of 0019-

